A vehicle shift control device is well known that employs a so-called shift-by-wire (SBW) system activating an electric motor based on a control signal to electrically switch shift positions related to running of a vehicle. For example, this corresponds to a motorcycle transmission control device disclosed in Patent Document 1. Specifically, the motorcycle transmission control device performs clutch operation and shifting operation by using power of an electric motor based on a shift command of a driver. If a driver frequently generates an unnecessary shift command by operation of a handy switch, the motorcycle transmission control device determines that the shift command is abnormal and cancels the shift command. This enables prevention of a temperature increase in an electric motor and over discharge of a battery due to the high-frequency energization of the electric motor.